This invention relates to inductor core-coil assembly for use as magnetic components in electric and electronic circuits such as converters, inverters, noise filters, resonant circuits, and the like.
Currently two types of magnetic cores are widely used in the inductive components in electric and electronic circuits such as AC-to-DC and DC-to-DC converters, inverters, filters for electronic noises, electronic resonant circuits and the like. One kind is a toroidally-shaped core with no physical gap and the other has at least one gap. In both cases, copper winding(s) must be applied on the core to form a magnetic inductor. When the required copper wire size is thin, the copper winding can be automated and equipment for such operation is available. However, due to the nature of this operation, such equipment requires a wire handling mechanism akin to that of a sewing machine which uses flexible threads. When the wire size is thick, such automated process becomes difficult and manual copper winding is a standard practice. It is therefore desirable to simplify the existing copper winding mechanism which enables to improve the winding productivity in general and eliminate the manual winding operation for the components requiring thick-gauge wires.
In accordance with the invention, there is provided a core-coil assembly and manufacturing thereof. A magnetic core has at least one physical gap and an insulated core assembly is formed by coating the gapped magnetic core with an electrical insulator or covering it with an insulating box having a physical gap whose dimension is close to that of the magnetic core gap. A copper wire passes through the gap of the core or the core assembly to be wound on the core or the core assembly. The copper-wire winding is also performed by rotating the core or the core assembly around the tangential direction of the circumference of the core or the core assembly. To improve magnetic performance of a gapped core, a non-conventional gap is introduced whose direction is off the radial direction of a toroidally wound core. The magnetically improved core with a non-conventional gap can be housed in a conventional core box with no gap and a copper winding may be applied on it to use it as in inductor. The copper winding part, on the other hand, can be prefabricated separately and a gapped core or core assembly is then inserted into the prefabricated coil through the gap. The gap section of the core or the core assembly may be filled with a magnetic or non-magnetic spacer during or after coil-winding operation. The core-coil assembling method of the present invention is much simpler than the existing method and thus is fully or semi-automated, improving core-coil assembly production yield with consistent performance.
The core-coil assembly manufactured in accordance with the method of the present invention is especially suited for use in such devices as power converters, inverters, electrical noise filters, electrical resonators, and the like.